INSECTA. 339 



individuals which form the greater portion of the community, and by 

 whose labour and vigilance the whole commiinity are maintained, 

 have been considered as being of neither sex. They have also been 

 designated by the terms of labourers and mides. It is now known, 

 however, that they are females, whose sexual organs or ovaries have 

 not been fully developed, and that if an amelioration of their diet 

 perfect those organs at a particular epoch while they are young they 

 become fruitful. 



The ova are sometimes hatched in the abdomen of the mother ; she 

 is then viviparous. The number of generations in a year depends on 

 the duration of each of them. Most commonly there is but one or 

 two. A species, all things being equal, is so much the more com- 

 mon, as one generation succeeds more rapidly to another, and as the 

 female is more prolific. 



A female Papilio or Butterfly, post coitum, lays her eggs, from 

 which are hatched, not Butterflies, but animals Avith an elongated 

 body, divided into rings, and a head furnished with jaws and several 

 small eyes, having very short feet, six of which are anterior, scaly, 

 and pointed, the rest varying in number and membranous, being 

 attached to the posterior annuli. These animals, caterpillars, live in 

 this state for a certain period, and repeatedly change their skin. An 

 epoch, however, arrives, when from this skin of a caterpillar issues a 

 totally diff"erent being, of an oblong form and without distinct limbs, 

 Avliich soon ceases to move and remains a long time apparently desic- 

 cated and dead under the name of a chrysalis. By close examination 

 we may discover on the external surface of this chrysalis, lineaments 

 which represent all the parts of the Butterfly, but under proportions 

 diff'ering from those they are one day to possess. After a longer or 

 shorter period, the skin of the chrrjsalis splits, and the Butterfly, 

 humid and soft, with flabby short wings, issues from it — a few mo- 

 ments, however, and it is dry, the wings enlarge and become firm, 

 and the perfect animal is ready for flight. It has six long legs, an- 

 tennae, a spiral proboscis, and compound eyes — in a word, it has no 

 resemblance whatever to the caterpillar, from which it has originated, 

 for it is ascertained that these various changes are nothing more 

 than the successive development of parts contained one within the 

 other. 



This is what is styled the metamorphosis of Insects. In their first 

 condition they are called larvce., in their second pupce or nymphs, and 

 in the third perfect insects. It is only in the last state that they are 

 capable of reproduction. 



All insects do not pass through these three states. Those which 



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